A product of Celtic's youth system,[3] McCart made his competitive debut for the Glasgow club as a substitute against Motherwell in the Scottish League Cup during August 2016.

[4] On 31 January 2017, McCart joined Inverness Caledonian Thistle on a loan deal until the end of the season.

[7] McCart moved on loan again in January 2018, joining Scottish League One side Alloa Athletic until the end of the season.

[11] Later in the month, Inverness and St Johnstone agreed a deal that allowed him to join the Saints immediately.

[2] He is the son of former Motherwell defender Chris McCart, who is now the Head of Celtic's Youth Academy.